1. Field of the Invention
The present invention relates to the field of acoustics, and in particular to a method and apparatus for suppressing wind noise.
2. Description of Related Art
When using a microphone in the presence of wind or strong airflow, or when the breath of the speaker hits a microphone directly, a distinct impulsive low-frequency puffing sound can be induced by wind pressure fluctuations at the microphone. This puffing sound can severely degrade the quality of an acoustic signal. Most solutions to this problem involve the use of a physical barrier to the wind, such as fairing, open cell foam, or a shell around the microphone. Such a physical barrier is not always practical or feasible. The physical barrier methods also fail at high wind speed. For this reason, prior art contains methods to electronically suppress wind noise.
For example, Shust and Rogers in “Electronic Removal of Outdoor Microphone Wind Noise”—Acoustical Society of America 136th meeting held Oct. 13, 1998 in Norfold, Va. Paper 2pSPb3, presented a method that measures the local wind velocity using a hotwire anemometer to predict the wind noise level at a nearby microphone. The need for a hotwire anemometer limits the application of that invention. Two patents, U.S. Pat. No. 5,568,559 issued Oct. 22, 1996, and U.S. Pat. No. 5,146,539 issued Dec. 23, 1997, both require that two microphones be used to make the recordings and cannot be used in the common case of a single microphone.
These prior art inventions require the use of special hardware, severely limiting their applicability and increasing their cost. Thus, it would be advantageous to analyze acoustic data and selectively suppress wind noise, when it is present, while preserving signal without the need for special hardware.